I know I have heard of this a number of times and it may have come up in the sauergut conversation because it would apply. I’m referring to adjusting the pH at the end of the boil. Who is doing this and what is the advantage of doing it? I see a few things saying that a pH of 5.0 is targeted. So maybe grab a small sample near the end of the boil, chill it and measure the pH and then if it’s high, add [whatever you use to lower pH] until you get to 5.0 and then chill your wort? Cheers and thanks.
I don’t do this pH adjustment yet, but I intend to experiment with it in the future. Some LODO enthusiasts occasionally advocate for this. What does it really do, why is important? I don’t know, I can’t remember.
The reason that kettle pH is high, is that it helps in the conversion of SMM to DMS and it helps with the utilization of hop bittering components. When you are brewing a beer with little or no pils malt (it has high SMM content), there isn’t really a reason to keep the kettle wort pH high (say around 5.4). When brewing without pils content, then its OK to target a kettle pH lower than 5.4. The only drawback is the slight reduction in hop utilization.
Why drop pH? Well you do want your wort and subsequent beer pH to be below the upper 4’s as soon as possible to assist in knocking out beer spoilers in the wort. Although yeast are the ultimate arbiters of where the beer pH will fall, helping out in getting the pH down may help the beer achieve a lesser pH. I’m not sure that’s always a good thing, but its a thing.
Thanks Martin. So target a flameout kettle pH of around 5.0 if someone were looking to do this?
Along with what has already been mentioned, lower pH helps with the protein break and also shortens yeast lag time which decreases the chances of oxidation before the ferment begins. When using sauergut it is thought that the flavor of LAB derived acidity is superior to the taste of yeast biological acids.
People often wonder why the German macros taste so different from beers produced in the rest of the world and these are just a couple of the many reasons.
I have done it a few times. A couple things I remember is you want to make the adjustment near the end the boil, not flameout, 10 mins left so the lower ph can be set to help finings such as Whirlfloc work better at the lower ph. I am lucky to see even a .1 or so ph drop naturally in the boil most times and I typically target 5.3-5.4 mash ph so that is where my boil also starts most times, occasionally starting even higher because of higher mash ph with darker beers.
I think the most common way of doing so is Lactic acid. I think the hardest part is getting a feel for or calculating just how much to add to hit your target. I don’t know if it may be the best approach but I have actually used the Sparge Water Acidification calculator in Bru’n Water for this boil ph drop with Lactic Acid and seems to get me close enough. I’m fine with anything between 5.0-5.3, I rather be on the lower end if I’m going through the trouble of doing it, but I don’t sweat it. I have noticed the benefits of clearer wort, helps produce much larger chunks that fall out better and easier. If it helps fermentation kick off faster, that’s always fine too. I don’t understand the science of it, mostly that the yeast will have to work less to begin to drop the wort ph.
Good stuff guys, thank you. I hope to brew here shortly and I will be thinking of this. My brewday last weekend was suspended due to a good, old-fashioned blizzard and this coming weekend it’s supposed to be below zero so… :
I’ve never cked my flameout pH but since y’all started talking about this I cked the hydrometer sample today: 5.27
And for the mash pH? Just wondering what to expect in the change; thinking that it was 5.3 or so?
At 20 min (my routine ck point) my mash pH was 5.2
[Edit: I’ve never concerned myself with the pH of the wort in the kettle. I’ve only focused on pH in the mash. I use a 20 min ck routinely in a 60 min mash.
I used to target 5.3 for lighter beers and 5.4 for darker beers at 20 min in the mash but I think I’ve convinced myself to go back to 5.2. I seem to get better wort clarity, conversion, and extract.
I figure if I am good in the mash I’ll be good in the kettle, fermenter, and keg.]
I shoot for between 5.0-5.2. As mentioned, put in the lactic acid prior to the finings.
I’m not sure that targeting a flameout pH of 5.0 is ideal, but I’ve heard of targeting 5.1 to 5.2.
Regarding a calculation for a flameout acid addition, I don’t believe that the Sparge Acidification calculator is ideal. That model doesn’t have the proper buffering. I suggest that brewers just look at the extra amount of acid needed to drop the MASH pH a tenth or two by using the Water Adjustment calculator. Do use the actual mashing water volume and all the original salt and acid additions, then increase that acid addition until it drops the mash pH the extra tenth or two that you want. Add just that additional amount of acid to the kettle. The kettle wort still has similar buffering as the wort does and this approach has worked decently for me. I welcome observations from others as to their pH reductions.
Great information. Thank you Martin.
I did exactly that a few times and the calculations worked out very well for dropping the pH to the level I wanted. I didn’t really see any improvement in the beer, though, so I stopped doing it.
The best possible hot break occurs during the boil when a (room temperature measured) Wort pH of 5.1 to 5.2 is achieved in the kettle just prior to adding finings (such as Irish Moss or Whirlfloc). With 5.2 being the ultimate ideal kettle pH target. 5.0 may be too low. And adjusting post boil at flameout may miss the hot break altogether.
Quoting the Crisp malting company:
[quote]pH also plays a key part in trub formation. The optimum pH for trub formation is 5.2, but the pH of the wort at the start of the boil can be between 5.8 and 5.9. The pH drops by around 0.2 units during the boil due to:
Melanoidin formation
Hop acids
Precipitation of phosphates and polyphenols by calcium
Release of H+ ions
To reduce the pH further, you can add phosphoric or lactic acid or calcium salts such as calcium chloride or calcium sulphate. Remember, Sulphate and Chloride remain in the wort and will add to the total levels in the beer. You will need to keep the ratios correct for the beer style you are producing.
[/quote]
I target the pH of lighter beers (Pils, Helles, etc) at the beginning of the boil. A boil pH of 5.0-5.2 keeps the beer from turning dark and still maintaining great malt character, basically it limits the maillard reaction. I have not seen any negative effects of boiling at lower pH’s. I do notice a difference in acid used to drop the pre-boil pH. Lactic acid will drop slightly during the boil and phosphoric will rise slightly. I’m no chemist, so I don’t know the reason for this. But it happens consistently.
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“… Sulphate and Chloride remain in the wort and will add to the total levels in the beer. You will need to keep the ratios correct for the beer style you are producing.”
Wonder how much remains. All? Some?
If some, do they both reduce by the same amount maintaining the ratio or do they remain at different amounts changing the ratio?
100% of the chloride and sulfate salts remain in the beer. I am pretty sure lactates stay in also. Phosphates largely precipitate out, which is one of the advantages of phosphoric (for some styles anyway).
Right. Calcium phosphate has limited solubility in water and will precipitate under the right circumstances. Sulfate and chloride don’t form insoluble compounds in wort AFAIK, and I wouldn’t expect them to come out of solution.
I do this only on beers with SRM lighter than about 6. For pilsner and helles styles I always add about 1mL lactic acid or so within the last 10 minutes of the boil.
I do this mainly because lager yeasts tend not to drop the pH as low and efficiently as ale yeasts. So usually on ales I don’t bother with the pH adjustment in the boil. Maybe I should though…
But after I started doing this I noticed a big difference in the finished beer on my pilsners and helles beers. I’m very unscientific about it so take that with a grain of salt.